Hindawi Publishing Corporation International Journal of Biomaterials Volume 2012, Article ID 397813, 14 pages doi:10.1155/2012/397813 Research Article Oligonucleotide and Parylene Surface Coating of Polystyrene and ePTFE for Improved Endothelial Cell Attachment and Hemocompatibility Martina Schleicher, 1 Jan Hansmann, 2 Bentsian Elkin, 2 Petra J. Kluger, 2 Simone Liebscher, 1 Agnes J. T. Huber, 1 Olaf Fritze, 1 Christine Schille, 3 Michaela M¨ uller, 2 Katja Schenke-Layland, 2, 4 Martina Seifert, 5, 6 Heike Walles, 2 Hans-Peter Wendel, 1 and Ulrich A. Stock 1 1 Department of Thoracic, Cardiac and Vascular Surgery, University Hospital, Hoppe-Seyler-Strasse 3, 72076 Tuebingen, Germany 2 Fraunhofer Institute for Interfacial Engineering and Biotechnology, Nobelstrasse 12, 70569 Stuttgart, Germany 3 Department of Prosthodontics, Section of Medical Materials and Technology, University Hospital, Osianderstrasse 2-8, 72076 T¨ ubingen, Germany 4 Inter-University Centre for Medical Technology (IZST), Eberhard Karls University, Silcherstrasse 7, 72076 Tuebingen, Germany 5 Institute of Medical Immunology, Charit´ e Universit¨ atsmedizin Berlin, F¨ ohrer Straße 15, 13353 Berlin, Germany 6 Berlin-Brandenburg Center for Regenerative Therapies (BCRT), Charit´ e Universit¨ atsmedizin Berlin, F¨ ohrer Straße 15, 13353 Berlin, Germany Correspondence should be addressed to Ulrich A. Stock, ulrich.stock@med.uni-tuebingen.de Received 15 July 2011; Revised 10 November 2011; Accepted 14 November 2011 Academic Editor: Rolf Larsson Copyright © 2012 Martina Schleicher et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In vivo self-endothelialization by endothelial cell adhesion on cardiovascular implants is highly desirable. DNA-oligonucleotides are an intriguing coating material with nonimmunogenic characteristics and the feasibility of easy and rapid chemical fabrication. The objective of this study was the creation of cell adhesive DNA-oligonucleotide coatings on vascular implant surfaces. DNA- oligonucleotides immobilized by adsorption on parylene (poly(monoaminomethyl-para-xylene)) coated polystyrene and ePTFE were resistant to high shear stress (9.5 N/m 2 ) and human blood serum for up to 96 h. Adhesion of murine endothelial progenitor cells, HUVECs and endothelial cells from human adult saphenous veins as well as viability over a period of 14 days of HUVECs on oligonucleotide coated samples under dynamic culture conditions was significantly enhanced (P< 0.05). Oligonucleotide-coated surfaces revealed low thrombogenicity and excellent hemocompatibility after incubation with human blood. These properties suggest the suitability of immobilization of DNA-oligonucleotides for biofunctionalization of blood vessel substitutes for improved in vivo endothelialization. 1. Introduction Current blood vessel replacement concepts, which use either prosthetic or biological grafts, achieve excellent mid-term results. The clinical application, however, is accompanied by a variety of limitations. Biological conduits (e.g., autologous greater saphenous vein) have better hemodynamic charac- teristics and avoid long-term anticoagulation but are limited in availability. On the long term, however, they fail due to intimal hyperplasia and fibrosis. Allograft transplants such as superficial femoral arteries have optimal hemodynamic properties, avoid any anticoagulation, and are resistant to infections to a certain extent. However, due to tissue scarcity, their availability is limited. In general, 5–30% of patients have no suitable autologous grafts available due to previous use or concomitant disease. In these cases, expanded polyte- trafluoroethylene (ePTFE) grafts are used. However, despite their prevalence, these grafts have a lower patency rate due to